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If there is a school of 250 people and they all flipped a coin approximately half would sit down because there are 2 sides to a coin and also a 50/50 chance. So, in a larger situation like 250 people there would be about 5-7 flips before the last person sits down. And in a smaller situation like 16 people there would be fewer flips like 3-5 before the last person sat down. So, we can conclude in most situations the bigger the amount of people the more flips until the last person sits down.